Device for feeding, removing and stacking workpieces

ABSTRACT

A device for feeding flexible workpieces into the workpiece clamping means of a sewing device and removing and stacking the same after sewing. A workpiece supporting plate is provided at least with one feed roller which cooperates with a workpiece holding means. The feed roller does not rotate during feeding the workpiece into the workpiece clamps of the sewing machine but is driven during the return movement of the supporting plate, thus moving the workpiece part carried thereon from the supporting plate and dropping it upon a swingable stacking rod.

United States Patent [1 1 Bernewasser et al.

[4 1 May 20, 1975 1 1 DEVICE FOR FEEDING, REMOVING AND STACKING WORKPIECES [75] Inventors: Horst Bernewasser, Steinhagen;

Hans Scholl, Lipperreihe, both of Germany [73] Assignee: Kochs Adler AG, Bielefield, Germany [22] Filed: Nov. 28, 1973 211 App]. No.: 419,690

[30] Foreign Application Priority Data Nov. 29, 1972 Germany 2258430 [52] US. Cl. 112/121.29 [51] Int. Cl. [105B 33/00 [58] Field of Search..... l12/12l.29, 121.15, 121.12, 1l2/l21.ll,2, 121.14

[56] References Cited UNITED STATES PATENTS Dale ..112/l21.29 X

3,099,970 8/1963 Hite l12/12l.l4 3,474,747 10/1969 Noiles ll2/l2l.l2

3,618,546 11/1971 Preston 112/l2l.29 3,722,436 3/1973 Strouse ll2/12l.29 X 3,769,924 11/1973 Rogers et al... 112/121.29 3,789,781 2/1974 Carson et a1 112/12l.12 X

Primary ExaminerWerner H. Schroeder Attorney, Agent, or Firm1acob L. Kollin [57] ABSTRACT A device for feeding flexible workpieces into the workpiece clamping means of a sewing device and removing and stacking the same after sewing. A workpiece supporting plate is provided at least with one feed roller which cooperates with a workpiece holding means. The feed roller does not rotate during feeding the workpiece into the workpiece clamps of the sewing machine but is driven during the return movement of the supporting plate, thus moving the workpiece part carried thereon from the supporting plate and dropping it upon a swingable stacking rod.

4 Claims, 5 Drawing Figures DEVICE FOR FEEDING, REMOVING AND STACKING WORKPIECES BACKGROUND OF THE INVENTION The invention relates to a device for feeding flexible workpieces into the workpiece clamps of a sewing device by means of a movable workpiece supporting plate, and for removing and stacking the same on a swingable stacking rod after termination of sewing.

There are already known automatic sewing units, in which, during the sewing of fabric cuts clamped in the workpiece clamps, the next following workpieces are placed on a movable workpiece support, aligned and clamped thereon, in order to be fed into the workpiece clamps by means of the workpiece support after opening the clamps, at which at the return movement of the workpiece support the sewn workpiece is removed and dropped upon a stack.

However, the aforesaid automatic sewing units of the hitherto known construction are only suitable for workpieces capable to be completely received by the workpiece clamps of the sewing units, so that only the marginal edges project from the clamping devices for forming the seam.

It is an object of the invention to provide resp. improve a mechanism of the above mentioned kind in that manner, that also fabric cuts, which, as a consequence of their length, are not capable to be completely received by the workpiece clamping devices, as for instance back parts of mens shirts to which two-piece yokes are to be sewn, may be positioned on a workpiece supporting plate movable to the workpiece clamps of the sewing unit, and that the workpieces to be sewn may be fed by means of said workpiece supporting plate into the opened workpiece clamps, at which already a short time prior to the return movement of the supporting plate the workpiece part carried thereon, is already dropped into the stacking device, whereas the workpiece part still in the sewing unit, drops automatically into the stacking device after termination of sewing.

SUMMARY OF THE INVENTION According to the invention this object has been substantially solved by the fact, that the workpiece supporting plate is provided at least with one feed roller or roll, which cooperates with a workpiece holding means, the feed roller does not rotate during feeding the workpiece into the workpiece clamps of the sewing unit but is driven during the return movement of the workpiece supporting plate, thus moving the workpiece part carried thereon from the supporting plate and dropping it upon the stacking rod.

In order to drive the feed rollers located below the workpiece supporting plate and projecting through recesses formed therein, there are provided a stationarily arranged toothed rack and a gear wheel meshing herewith. The gear wheel is formed with a freewheeling, in order to drive the feed rollers in one direction of rotation by means of a shaft pivoted to the workpiece supporting plate,

Further features of the invention may be obvious from the accompanying drawings and the following description.

One embodiment of the invention is illustrated in the drawings, in which FIG. 1 is a perspective view of the essential parts of the mechanism according to the invention, and

FIGS. 2 to 5 are diagrammatic representations for illustrating the operation of the mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENT The sewing unit 1 diagrammatically represented in the drawings, comprises a sewing machine 2 which is guided in a not further described manner and according to the desired seam along the workpiece clamps 3 of the sewing unit 1. The workpiece clamps 3 comprise an upper clamping plate 4, a lower clamping plate 5, a bracket 6 and a lifting cylinder 7 for closing and opening the two clamping plates 4, 5. The bracket 6 is pivoted to the lower clamping plate 5, whereas the upper clamping plate 4 is articulated to the bracket 6.

Further, the automatic sewing unit 1 is provided with a feeding device 8 substantially comprising a workpiece supporting plate 9, which is capable of being partly moved into the opened workpiece clamps 3.

The workpiece supporting plate 9 receiving upon its upper surface a workpiece 10, is provided with recesses 11 through which are projecting feed rollers 12 having a non-skid cover, in order to engage the bottom surface of the workpiece 10. The feed rollers 12 pivoted about an axis 13 to the workpiece supporting plate 9, are connected with toothed belt wheels 14 which are in driving connection via toothed belts l5 and additional toothed belt wheels 16 with a shaft 17 also pivoted below the workpiece supporting plate 9.

To each feed roller 12 is associated 'a workpiece holding means 24 having a loose roller 18 pivoted in a fork 19. The fork 19 is provided at an U-shaped bar 20, which is capable to be lifted and lowered by means of an air cylinder 21 via a linkage 22 and a shaft 23, in order to lift or press the loose roller 18 from or upon the feed rollers 12. The air cylinder 21 is located below the workpiece supporting plate 9. v a

At one end the shaft 17 carries a gear wheel 25 meshing with a gear rack 26, which is stationarily mounted to the sewing unit 1. Secured to the shaft 17 is a freewheeling 27 located in the gear wheel and causing the rotation of the shaft 17 only at the return movement of the workpiece supporting plate 9 from the workpiece clamps 3. At the free end of the shaft 17 is arranged a shaft brake 28 comprising a brake wheel 29 secured to the shaft 17, a brake band 30 and a tension spring 31, in order to render more difficult the rotation of the feed rollers 12.

A baffle 31 extends from the workpiece clamps 3 to a swingable stacking bar 32, located below the plane of the workpiece supporting plate 9 in the clearance between the latter and the workpiece clamps 3. The baffle 31 is formed with recesses 33 for the passage of the feed rollers 12 when the workpiece supporting plate 9 is moved into the workpiece clamps 3.

Operation of the mechanism may be described as follows:

By pressurizing the air cylinder 21, the loose rollers 18 are lifted from the feed rollers 12, in order that the workpieces to be sewn together may be placed on the workpiece supporting plate 9. After aligning of the lat ter the loose rollers 18 are lowered, thus clamping the workpieces 10, 10' therebetween and the feed rollers 12 (FIG. 2).

During the now following feed of the workpiece supporting plate 9 into the opened workpiece clamps, the shaft 17 is not driven as a consequence of the influence of the freewheeling 27, but the gear wheel 25 rolls along the gear rack 26 (FIGS. 1 and 3).

Subsequently, the upper clamping plates 4 of the workpiece clamps 3 are lowered upon the lower clamping plates 5 for clamping the workpieces 10, the workpiece supporting plate 9 is removed and simultaneously the sewing machine is operated, which moves during the sewing of the workpieces 10, 10' from the right to the left. During the return movement of the workpiece supporting plate 9 the feed rollers 12 are driven in the direction of the arrow (FlG. 4), so that still before returning of the workpiece supporting plate 9 in its start position, the part of the workpiece 10 still placed thereon, is moved from the workpiece supporting plate 9 and dropped into the dot-lined position (FIG. 4) at the stacking rod 32, whereas the other part is still clamped in the workpiece clamps 3.

During this time, the stacking rod 32 is swung into the position dot-lined in FIG. 4.

After termination of sewing the workpiece clamps 3 are opened and the hitherto clamped part of the workpiece 10 slides downwardly along the baffle 31 and is received by the stacking rod 32 (FIG. 5).

What we claim is:

1. In combination with a sewing device having a sewing machine and workpiece clamping means, means for feeding flexible workpieces into said workpiece clamping means and removing the same after sewing, comprising a workpiece supporting plate means for moving said workpiece support plate in the direction to and from said workpiece supporting plate, said swingable holding means for clamping a workpiece during moving to said workpiece clamping means and releasing and displacing of said workpiece from said workpiece support plate during the removing of the same in an opposite direction, and stacking means including an oscilatable stacking rod for stacking means for oscillating said stacking rod in timed relationship to the releasing of said workpiece clamping means and said workpiece holding means, and said workpiece wherein said workpiece supporting plate is provided with recesses and said workpiece holding means comprises feed rollers pivoted below said workpiece supporting plate and penetrating said recesses, rotary pressure rollers arranged above said workpiece holding means and cooperating with said feed rollers, lifting and pressing means attached to said workpiece supporting plate for pressing said rotary presser roller against said feed rollers, and driving means for said feed rollers, said feed rollers being non-rotatable when moving said workpiece supporting plate in a direction to said workpiece clamping means of said sewing device and being rotatable when moved in a contrary direction.

2. The combination of claim 1, wherein said driving means for said feed rollers comprise a stationary gear rack, a gear wheel meshing with said gear rack, a freewheel within said gear wheel, a shaft pivoted below said workpiece supporting plate and receiving said freewheel with said gear wheel, belt pulleys attached to said shaft, belt pulleys attached to said feed rollers, endless belts connecting said belt pulleys, and an adjustable brake means actuating upon said shaft.

3. The combination of claim 1, wherein each of said lifting and pressing means comprise a lever arm having a forked part for receiving said rotary presser rollers, a shaft pivoted below said workpiece supporting plate and carrying said lever arm, and a driving means for actuating said lever arm.

.4. The combination of claim 1, wherein said oscillatable stacking rod is disposed in a plane being below said workpiece holding means and between said workpiece clamping means and said stacking means further includes a workpiece baffle extending from said workpiece clamping means to said stacking rod. 

1. In combination with a sewing device having a sewing machine and workpiece clamping means, means for feeding flexible workpieces into said workpiece clamping means and removing the same after sewing, comprising a workpiece supporting plate means for moving said workpiece support plate in the direction to and from said workpiece supporting plate, said swingable holding means for clamping a workpiece during moving to said workpiece clamping means and releasing and displacing of said workpiece from said workpiece support plate during the removing of the same in an opposite direction, and stacking means including an oscilatable stacking rod for stacking means for oscillating said stacking rod in timed relationship to the releasing of said workpiece clamping means and said workpiece holding means, and said workpiece wherein said workpiece supporting plate is provided with recesses and said workpiece holding means comprises feed rollers pivoted below said workpiece supporting plate and penetrating said recesses, rotary pressure rollers arranged above said workpiece holding means and cooperating with said feed rollers, lifting and pressing means attached to said workpiece supporting plate for pressing said rotary presser roller against said feed rollers, and driving means for said feed rollers, said feed rollers being non-rotatable when moving said workpiece supporting plate in a direction to said workpiece clamping means of said sewing device and being rotatable when moved in a contrary direction.
 2. The combination of claim 1, wherein said driving means for said feed rollers comprise a stationary gear rack, a gear wheel meshing with said gear rack, a freewheel within said gear wheel, a shaft pivoted below said workpiece supporting plate and receiving said freewheel with said gear wheel, belt pulleys attached to said shaft, belt pulleys attached to said feed rollers, endless belts connecting said belt pulleys, and an adjustable brake means actuating upon said shaft.
 3. The combination of claim 1, wherein each of said lifting and pressing means comprise a lever arm having a forked part for receiving said rotary presser rollers, a shaft pivoted below said workpiece supporting plate and carrying said lever arm, and a driving means for actuating said lever arm.
 4. The combination of claim 1, wherein said oscillatable stacking rod is disposed in a plane being below said workpiece holding means and between said workpiece clamping means and said stacking means further includes a workpiece baffle extending from said workpiece clamping means to said stacking rod. 